Hail and wind gusts to 40 miles an hour are possible from a strong thunderstorm moving through northern Hunterdon County around 4:30 p.m.

The storm was moving north, headed into Warren, Morris and Sussex counties, the National Weather Service said.

“Frequent cloud-to-ground lightning is occurring with this storm,” NWS said. “Do not stay in the open nor seek shelter under trees when lightning threatens. Move indoors when a thunderstorm approaches.

Very heavy rain will fall from this storm, causing water to pond on roads and fill poor drainage areas. The rain can cause rapid rises on small streams and creeks, the service added.